In celebration of the holiday season, University of the Philippines‘ Office of Public Affairs launched a star-studded video of UP alumni lending solidarity to their alma mater by doing one simple thing: reciting their student numbers.

In the nearly 4-minute video uploaded on YouTube, celebrity alumni like Jessica Soho, Karen Davila, Atom Araullo, Former President Fidel V. Ramos, Senator Grace Poe and Eraserheads remember their student numbers many years, even decades, after they graduated.

The student number is more than a serial number assigned to all incoming freshmen. It is a confirmation of one’s acceptance into the institution. It is also used for everything from enrollment to tracking grades. You write it on your paper whenever yo take the exam or submit your research paper. The first few digits reveal the year you entered university. So if you want to know the age of these celebrity alumni, take note of their student numbers.

For the alumni, remembering the student number brings back memories of UP. It is truly a #TatakUP.